PITTSBURGH — They build on you, these Rangers do, competing, squeezing about as much as there is from their bodies, their hearts and their talents in grinding their way through the schedule against teams more skilled but no more committed.

Black-and-Blueshirts in more ways than one, the Rangers survived another loss of an upper-echelon player when Ryan Callahan went down with a broken left hand, blocking a shot 4:42 into the match, persevering to beat the Penguins 4-1 last night on a four-goal explosion in the final 10 minutes.

That makes seven victories in the past 10 games for the Rangers, including the past two over Winter Classics Washington and Pittsburgh.

One game at a time is the mantra, the next one tonight at the Garden against Phoenix, but when the Rangers look in the mirror, they are pretty pleased with the reflection, as they have every right to be.

“We talked about that, how we were beginning to be respected around the league for our hard work, and we saw it as a great challenge and great opportunity to face those two teams,” said Henrik Lundqvist. “We know the Caps and Penguins are Cup contenders, and for us to beat them, it just reinforces our belief in our style and our system and in ourselves.”

Callahan, likely to be sidelined in the range of six weeks, went out just as Chris Drury, previously sidelined for 31 of the first 32 matches with a broken finger, played for the first time since Oct. 15. The captain played 14:32 with coach John Tortorella maniacally shuffling combinations.

“It was great to have him back, blocking shots,” Tortorella said. “He’s got [guts] as big as a building.”

The Rangers were extremely conservative through the first two periods in focusing on preventing the odd-man rushes that burned them in the Penguins’ 3-1 victory at the Garden on Nov. 29. They succeeded in that objective, but rarely had the puck and trailed 1-0 on Evgeni Malkin’s gorgeous goal off a brilliant feed from Sidney Crosby in the dying seconds of the first period.

“I don’t want to say we were too cautious; we stayed within our structure and trusted one another with the third guy high, but we knew we need to have the puck more,” said Brian Boyle, who scored the final goal, was matched much of the night against Crosby and seemed to be in the middle of everything. “We had an extra step in the third, kept taking the body and executed.

“The thing is, we know it’s a 60-minute game.”

The Rangers tied the score on Erik Christensen’s wicked left-circle wrist shot on the power play at 10:10. Christensen played only 7:41 and was otherwise barely noticeable, but the shot that beat Brent Johnson served as yet another example of why he can be so valuable, albeit so frustrating.

It took only 25 seconds for the Rangers to grab the lead on Alex Frolov’s goal in front on a play that Boyle initiated from the left corner. Artem Anisimov scored at 14:55 before Boyle closed it at 16:29, for four goals within 6:19.

“Another step in the right direction,” said Tortorella. “These two wins over really good teams, I think it’s a pretty big step, as a team, not as individuals, and that’s how we have to play.”